Recorded music pitch and tempo adjustment indicating device



Jan. 3, 1939. K, R055 2,142,591

RECORDED rmsm PITCH AND TEMPO ADJUSTMENT mmcmme DEVICE Filed Aug. 16,19:7

QJNYENTORQ BY hmq -libs-s ATTORNEY.

Patented Jan. 3, 1939 1 TED s'riirss PATEN OFFICE INDICATING' DEVICERECORDED MUSIC PITCH AND TEMPO AD- JUSTMENT liingltoss, Jackson Heights,Long Island, N. Y. Application August 16, 1937, Serial No. 159,256

5Claims.

The purpose oi'this invention is to provide an improvement in phonographrecords, in which the speed at which the record is reproduced may be setto correspond with the speed at which 5 the record traveled when made,and in which -means is provided for determining the exact instant atwhich the record will start to play.

Theinventio'n is a phonograph record oi'the conventional type havingadditional grooves in which a constant frequency is recorded, and also--means:in the starting groove for producing beats atregular intervalsbefore the record starts to 7 .25 must revolve to reproduce themusic'atthe same Ditch that it was originaliy'recorded.

To provide means andapparatus to aurally indicate by comparison to atuning fork, or-

specifically pitchedn'ote sounded on any musical so, instrument, thespeed at which a phonograph record was recorded, whereby, with thisknowledge, the speed of the reproducing machine may be" adjusted "toreproduce the recorded music at the proper pitch. v 35 To provide meansand apparatus to indicate the tempo at which a musical composition wasoriginally recorded.

To provide means and apparatus for recording a sub-audible frequencywith relatively high am- 40 plitude peaks of relatively short durationat each cycle, these peaks being audible.

To provide means and-apparatus i'orre'cording a remilarly recurringclick or beat which corresponds to the tempo or meter of the.com-

{a position recorded,

To provide means and apparatus for adjusting the speed of a phonographrecord so that reproduced indicating tempo clicks are of the samefrequency they were originally recorded.

so To means and method whereby, upon reproducing a phonograph record,the exact moment at which the recorded music will. begin can be-anticipated. To provide'means and 'apparatus.whereby a llphonographjreccrd may be tuned so that-the nously controlled motors.

reproduced music will be played at the same pitch as it was originallyrecorded, thereby allowing a musician to play his instrument along withthe reproduced music, and in exact pitch with aforesaid music.

To provide means and apparatus whereby a' musician may. turn aphonograph record to the pitch of his instrument. automatically causingrecorded tempo beats to become reproducible,

so that the musician may know in advance, that, 10 upon reproducing saidrecord, he may know the exact moment at which the recorded music willstart, and that he will, upon playing his instru- I ment along with therecorded music, be in ex-' act tune with it. 16

To provide a pitch indicating device upon a phonograph record. Toprovide a tempo indicating device upon a phonograph recdrd.

. To provide a pitch and tempo indicatingde- 20 vice upon a phonographrecord.

To provide means and apparatus whereby a listener of a phonograph recordmay adjust his phonograph turntable, independently of the speed markerupon the motor governor, so that a recorded symphony or other recordedmusic will be reproduced in proper pitch.

With these ends in view the invention embodies a phonograph recordhaving an extended -starting groove, with means producing regular beatstherein before the .record starts to play,

and additional center grooves recorded at regular frequencycorresponding with the speed at which the record was made.

The drawing shows a plan view of a record embodying these features. Itmay be readily appreciated that present dayphonograph recordingapparatus may be adjusted. accurately to a standard speed; This isgenerally done with a synchronousmotor or synchro The turntablespeedgenerally adopted is 78 revolutions per minute. To reproduce thefinished records so that-the music is played at exactly the same-pitchaswas- 45,

recorded. it is necessary that the reproducing turntable revolve atexactly the same number of revolutions per minute as the recordingturntable revolved when the music was originally recorded.

Nowyif a synchronous rcprod cing motor is geared to the same speed, say7 R. P. M., as the recording turntable. the music will automaticallybe-reproduced at the same pitch. But in using any other type oireproducing turntable vmotor, which usually has a speed control lever,

7 And also should the reproduction turntable turn at 77 instead of '78,the equation wouldbecome:

e 78n=33880 a==434.3

the playing of musicians who wish Federation of Musicians pitch at.which itwas recorded.

. There is, at present, no convenient way of adjusting the speedpositively. Although there are etched marks on an indicating plate,which is generally set under a pointer on the speed control lever, themarxings (indicating revoluare more or less arbitrary, and

My invention is primarily intended for musiclans who either desire toplay their own instrument along with the reproduced music. or who wishto be sure they are played in proper pitch.

It is also intended for music students or other to use my invention uponwhich patent is now pending, Serial Number 156,303, which consists of aphonograph record upon. which the accompaniment only is recorded. Since,in one form of this invention above mentioned, student exercises areharmonized, this accompaniment being recorded upon the phonoit isabsolutely necessary that the at the identical speed graph disc,reproduction be eifected at which it was recorded.

As an example of the relation of turntable speed to the musical pitch,allow me to illustrate with an equation: A440 is the standard pitchadopted by the United States Government in 1920, and also the oiiicialpitch of the American since 1917. If A440 is recorded at 7'8 R. P. M.,and reproduced at 79 R. P. M., the equation will become:---

,So, as will be seen, the recorded A440 wil become upon reproductionA445.

Since French pitch is A435, and this reproduced A4343 is even lower, thedifference would be immediately noticeable by a musician, .andespecially if he were to attempt to play along with the reproducedmusic.

Another feature of my invention is the way in which the tempo or meterof the recorded music is indicated in advance, so that a student, aboutto play an exercise or study along with the recorded accompaniment, mayknow the exact time to begin playing.

Numeral l indicates a phonograph record disc containing upon and withinits surface a spiral groove having recorded thereupon, and therein,music, recorded in to the art. Numeral 2 indicates the entrance to theinitial spiral groove, shown here as being the outermost groove. In somerecordings this initial groove is the innermost, ,the phonographreproducer traveling then from inside to outside. But, as I have shown,the phonograph reproducer,

travel from the outside toward the center during the record. Theturntable and record in this instance will revolve clockwise. Thereproducer needle will first encounter the at a constant rate, and

listening to the music.

the manner commonly known irregularity shown at I, which irregularitywill cause a click to be reproduced, at 4 another click is produced,another at 0, and still another click will be produced at 6. At 1 therecorded musical composition will begin. The angular or radialseparation between the irregularities I, l, 5, 0, and the point I wherethe recorded music will commence to be reproduced, is equal.

As will be seen, when the record is revolving the reproducing needle isfollowing the groove starting at entrance 2, there will be, in thiscase, four evenly measured .clicks produced by irregularities 3, 4, 5,and B,

' at the exact point where the recorded music begins.

The grooves as followed by the needle from the beginning of the recordedmusic 1, to a point between I and 8, constitute the body of the record;the musical subject matter. At I is shown the customary more rapidspiral for the purpose of carrying the reproducer to a concentric groovenear the center of the record. This is normally for the purpose ofcausing the reproducer, in its more rapid rate of travel at that point.to actuate an automatic motor cut-of! of some common type, and is knownto the art.

At numeral 9 is shown a separate spiral, not essentially connected tothe main grooves which are indicated as lying between points 2 and 8.This separate spiral 9 consists of several turns of a spiral, and isshown in the drawing as terminating in a concentric groove in. In thisspiral I have recorded a constant frequency, A440 for example, and thisA440. having been recorded upon the master, and having been used also asa reference to which the musicians, who played for the recording, tunedtheir instruments, this inner spiral, starting at 8, will uponreproduction sound the master tuning note' of the recorded music.

may speed up or slow down the turntable speed until unison between thereproduced frequency and the tuning fork is effected. when this is done,the reproduced music automatically will be played in proper pitch, andthe four initial clicks or beats will occur-in, the correct timeintervals.

It will be appreciated that I may choose any frequency as=a standard,and synchronism may be effected by comparison to a tuning fork of thefrequency chosen, although, since the United States Government andAmerican Federation of Musicians have ofll'cially adopted A440 as astandard, I prefer to use this frequency.

The use of the fork may be obviated where the musician's instrument maybe above or below this standard, in which case he will sound the A, ortuning note, on his instrument, and

